Many liquid substances, including pharmaceutical and veterinary preparations, substances for medical use, chemical reagents and numerous other substances need to be dispensed from a storage container, particularly sterile storage containers, in such a way that the remaining contents are not contaminated. Any system used for dispensing, for example, sterile substances, must be designed such as to ensure the substance being dispensed remains sterile, as well as minimising the possibility of contamination of any sterile substance remaining in the container. In many instances, it is necessary to dispense only a portion of the quantity of material stored in a container in a way that the container is resealed for subsequent dispensing of additional, uncontaminated substance.
It has been common practice to dispense liquid substances from sterile containers by extracting the substance using a syringe having a needle which is caused to pass through a resilient stopper on the container whereby the contents may be extracted through the needle into the syringe. The syringe may then be used to dispense the substance, either by injecting the substance into a patient, or an animal or any other container or body to which the material is to be dispensed. With such a dispensing system, the resilience of the stopper material seals the hole created by insertion of the needle through the stopper to thereby maintain the contents of the container in a sterile condition. However, by using a needle and syringe dispensing system in conjunction with a resilient container stopper, it is difficult to extract all the contents of the container and, therefore, it is common for some proportion of the container contents to be discarded and wasted. When the container contents comprise a relatively expensive pharmaceutical, veterinary product, chemical reagent or the like, the cost associated with discarding a portion of the container contents may be considerable.
In many instances, substances must be dispensed using a delivery system which does not involve the use of a needle. Heretofore, however, it has been common practice to use a needle to extract the substance from a container and to then discard the needle, or remove the needle from the syringe body and thereafter use the syringe, without the needle, to dispense the product. However, the handling of syringe needles inevitably gives rise to risks associated with accidental needle stick or inadequate or improper or unsafe disposal of the discarded needle. Accordingly, the use of a needle to facilitate extraction of the contents of a container when the needle is not to be used to dispense those contents is undesirable and, potentially, inefficient.
It is therefore desirable to provide a dispensing system which alleviates at least some of the disadvantages of existing dispensing systems.
It is also desirable to provide a dispensing system including a closure for a container that facilitates extraction of a fluid from the container in a manner that minimises risk of contents contamination.
It is also desirable to provide a dispensing system that may be used without the use of a needle to extract contents of a container.
It is also desirable to provide a dispensing system which minimises the risk of contamination of the contents of a container.
It is also desirable to provide a closure for containers storing a fluid whereby the fluid content is able to be removed by more than one extraction method a manner to minimise contamination of remaining contents.
It is also desirable to provide a closure for a container, particularly a container of a sterile liquid, which is economic to manufacture, is simple to use and facilitates dispensing of the container contents.